| Message ID | 1431632467-2000-1-git-send-email-fdmanana@suse.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Thu, May 14, 2015 at 08:41:07PM +0100, Filipe Manana wrote: > When we clear an extent state's EXTENT_LOCKED bit with clear_extent_bits() > through free_io_failure(), we weren't waking up any tasks waiting for the > extent's state EXTENT_LOCKED bit, leading to an hang. > > So make sure clear_extent_bits() ends up waking up any waiters if the > bit EXTENT_LOCKED is supplied by its callers. > > Zygo Blaxell was experiencing such hangs at inode eviction time after > file unlinks. Thanks to him for a set of scripts to reproduce the issue. Good catch! Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Thanks, -liubo > > Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> > Signed-off-by: Filipe Manana <fdmanana@suse.com> > --- > fs/btrfs/extent_io.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index c32d226..856c2e8 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -1277,7 +1277,12 @@ int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, > int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, > unsigned bits, gfp_t mask) > { > - return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask); > + int wake = 0; > + > + if (bits & EXTENT_LOCKED) > + wake = 1; > + > + return clear_extent_bit(tree, start, end, bits, wake, 0, NULL, mask); > } > > int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end, > -- > 2.1.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index c32d226..856c2e8 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -1277,7 +1277,12 @@ int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end, unsigned bits, gfp_t mask) { - return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask); + int wake = 0; + + if (bits & EXTENT_LOCKED) + wake = 1; + + return clear_extent_bit(tree, start, end, bits, wake, 0, NULL, mask); } int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
When we clear an extent state's EXTENT_LOCKED bit with clear_extent_bits() through free_io_failure(), we weren't waking up any tasks waiting for the extent's state EXTENT_LOCKED bit, leading to an hang. So make sure clear_extent_bits() ends up waking up any waiters if the bit EXTENT_LOCKED is supplied by its callers. Zygo Blaxell was experiencing such hangs at inode eviction time after file unlinks. Thanks to him for a set of scripts to reproduce the issue. Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Signed-off-by: Filipe Manana <fdmanana@suse.com> --- fs/btrfs/extent_io.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)